Speculations over at this Japanese blog seem to indicate that Operate Shooting Star is not a crossover, but a remake of the original Rockman EXE game featuring Shooting Star Rockman styled controls and gameplay. In other words, the game will "operate" like a typical SSR title.
To back this up, the blogger points out that the logo for Operate Shooting Star is similar to that of Rockman EXE 1's (picture)
Hm... Your thoughts?
Also, you guys might want to take a gander at Heat Man's thoughts over at the Mega Man Network. He presents some really interesting points that suggest a crossover instead of a "remake." Read up on it over here.